1. Technical Field
The present invention relates to a content retargeting method and apparatus, more particularly to a content retargeting method and apparatus using axis-aligned importance scaling.
2. Description of the Related Art
In step with advances in mobile devices and various display devices, there is a growing interest in N-screen services that use various displays to provide a service in the form of the same application.
For this, a technology is needed which, rather than encoding visual multimedia objects in independent forms for TV, films, mobile devices, etc., as in the past, instead arranges multimedia objects having a single type of source across various display devices.
One problem in thus applying multimedia over various displays is that each display device will have a different resolution and different aspect ratio. In the related art, all portions of an image are reduced equally according to the resolution and aspect ratio of the target display, without considering the problem above, so that the visually characteristic portion on the screen or information having high importance may not be preserved and may often be lost.
As such, in order to effectively transfer the image information for screens having different resolutions and aspect ratios, retargeting techniques have been proposed which reduce the size of an image according to the size of the target display while minimizing distortions in important areas of the image.
One example of a retargeting technique is the seam carving technique, which can reduce the size of an image by using an optimization method based on dynamic programming techniques to iteratively find and remove seams that have low importance.
However, conventional retargeting techniques such as the seam carving technique may remove unimportant portions excessively and consequently can cause unintended distortions. Such retargeting techniques may also entail calculations of high complexity and thus may require longer times for the calculations. There is also the limit of having to rely on hardware such as the GPU to achieve real-time performance.